Condensation products of phenol and salicylaldehyde

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 July 2019 to 14 August 2019

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Radiolabelling:

no

Analytical monitoring:

yes

Details on test conditions:

The Test Solutions were kept between 49.8 – 50.3 °C.

HYDROLYSIS – TIER 1
5 – 5 tubes with test media (at all pH levels) were spiked with the spiking solution. All tubes were sampled after dissolution of the test material (Day-0) and the samples were processed as described above. 1 – 1 control tubes at all pH levels were also prepared (test buffer without spiking) to check the potential interfering components from the buffer. The test solutions and control test buffer were incubated at 50 °C for 5 days. After the incubation period all tubes were sampled again both control tubes were sampled, processed and measured.

CALCULATIONS
To determine the test item concentration in the saturated solutions the following calculations were applied:
The concentration of the test solution was calculated using the following equation:

CTestSol = ((Peak Area Average – Intercept) / Slope) x AnDil

Where:
cTestSol is the test item concentration in the test solution (mg/L)
Intercept is the intercept of the calibration curve
Slope is the slope of the calibration curve
AnDil. is the dilution of the analytical sample after the enrichment

The stability was determined:

Stability % = (ci / C0) x 100 %

Where:
c0 and ci are the test item concentrations measured on the initial and the end point of the experiment (mg/L)

Duration:

5 d

pH:

4

Temp.:

50 °C

Initial conc. measured:

ca. 1 000 mg/L

Duration:

5 d

pH:

7

Temp.:

50 °C

Initial conc. measured:

ca. 1 000 mg/L

Duration:

5 d

pH:

9

Temp.:

50 °C

Initial conc. measured:

ca. 1 000 mg/L

Number of replicates:

Six replicates per pH.

Positive controls:

not specified

Negative controls:

not specified

Preliminary study:

The test solutions were kept between 49.8 – 50.3 °C.
At pH 4 the mean stability from 6 replicates was 101.0 % (1.3 % RSD).
At pH 7 the mean stability from 6 replicates was 100.8 % (1.6 % RSD).
At pH 9 the mean stability from 6 replicates was 98.6 % (1.0 % RSD).
The test material is hydrolytically stable at 50 °C.

Transformation products:

not measured

% Recovery:

100

St. dev.:

1.3

pH:

4

Temp.:

50 °C

Duration:

5 d

Remarks on result:

hydrolytically stable based on preliminary test

% Recovery:

100

St. dev.:

1.6

pH:

7

Temp.:

50 °C

Duration:

5 d

Remarks on result:

hydrolytically stable based on preliminary test

% Recovery:

98.6

St. dev.:

1

pH:

9

Temp.:

50 °C

Duration:

5 d

Remarks on result:

hydrolytically stable based on preliminary test

Remarks on result:

hydrolytically stable based on preliminary test

Summary of the Results

Sample	pH	CDay-0 (mg/L)	CDay-5 (mg/L)	Stab (%)	Mean Stab (%)	RSD%
ST-202-HYD1-TS-410	4	0.00	< LOQ	N/A	N/A	N/A
ST-202-HYD1-TS-411	4	26.43	26.71	101.1	101.0	1.3
ST-202-HYD1-TS-412	4	26.27	26.57	101.1
ST-202-HYD1-TS-413	4	26.19	25.86	98.7
ST-202-HYD1-TS-414	4	25.97	26.49	102.0
ST-202-HYD1-TS-415	4	26.43	26.95	102.0
ST-202-HYD1-TS-710	7	0.00	< LOQ	N/A	N/A	N/A
ST-202-HYD1-TS-711	7	26.06	26.27	100.8	100.8	1.6
ST-202-HYD1-TS-712	7	25.89	26.52	102.5
ST-202-HYD1-TS-713	7	26.55	26.30	99.1
ST-202-HYD1-TS-714	7	27.02	26.82	99.2
ST-202-HYD1-TS-715	7	26.21	26.79	102.2
ST-202-HYD1-TS-910	9	0.00	< LOQ	N/A	N/A	N/A
ST-202-HYD1-TS-911	9	25.88	25.09	96.9	98.6	1.0
ST-202-HYD1-TS-912	9	27.07	26.80	99.0
ST-202-HYD1-TS-913	9	26.11	25.88	99.1
ST-202-HYD1-TS-914	9	26.66	26.39	99.0
ST-202-HYD1-TS-915	9	26.60	26.31	98.9

 

Validity criteria fulfilled:

not specified

Conclusions:

Under the conditions of the study the test material is hydrolytically stable in the range pH 4 – 9.

Executive summary:

The hydrolytic properties of the test material were assessed according to OECD Test Guideline 111 and in compliance with GLP using an HPLC method.

Six replicates were conducted at pH 4, pH 7 and pH 9.

Tubes with test media (at all pH levels) were spiked with the spiking solution. All tubes were sampled after dissolution of the test item (Day-0) and the samples were processed as described above. Control tubes at all pH levels were also prepared (test buffer without spiking) to check the potential interfering components from the buffer.

The test solutions and control test buffer were incubated at 50 °C for 5 days. After the incubation period all tubes were sampled again both control tubes were sampled, processed and measured.

Under the conditions of the study the test material is hydrolytically stable in the range pH 4 – 9.

Description of key information

Under the conditions of the study the test material is hydrolytically stable in the range pH 4 – 9.

Additional information

The hydrolytic properties of the test material were assessed according to OECD Test Guideline 111 and in compliance with GLP using an HPLC method.

Six replicates were conducted at pH 4, pH 7 and pH 9.

Tubes with test media (at all pH levels) were spiked with the spiking solution. All tubes were sampled after dissolution of the test item (Day-0) and the samples were processed as described above. Control tubes at all pH levels were also prepared (test buffer without spiking) to check the potential interfering components from the buffer.

The test solutions and control test buffer were incubated at 50 °C for 5 days. After the incubation period all tubes were sampled again both control tubes were sampled, processed and measured.

Under the conditions of the study the test material is hydrolytically stable in the range pH 4 – 9.